I am not a big fan of night hiking or to be more accurate night scrambling. However, on Thursday evening I scrambled to the top of Kraft Mountain with Meetup.com. We made it to the top and across the ridge before it got dark. As we started down the descent gully the last light faded into the night. We turned on our headlamps and started down the gully. It was kind of surreal as I turned around to see a sea of headlamps above. Although this was very different and fun, I can not recommend scrambling at night.
I always carry a headlamp in my pack. Without a headlamp, I could not have made it down the gully. I do not find it dangerous to hike a trail at night. During some of my Sierra trips I have gotten started before sunrise. Currently it gets dark at 7 pm. Starting in October the Scenic Loop drive at Red Rock Canyon was close at 7 pm. It closes at 8 pm through the end of September.